British police set up roadblocks Tuesday to try to hinder scavengers who descended on a southwest England beach to pick through shipping containers that washed ashore from a stranded cargo vessel.

Police acknowledged that the scavengers' activity was legal as long as they returned the cargo to its lawful owner, but attempted the cordon anyway — with limited success.

"No matter what people think about it, there have been no public order offenses, and people are going about it in a good-natured way," Devon and Cornwall police spokesman Terry Hodgson said.

Britain's coast guard, meanwhile, finished repairing a fuel tank that had leaked as much as 50 tons of oil into the water in an area designated by UNESCO as a World Heritage site. At least 900 seabirds were found covered in oil, according to the Royal Society for the Protection of Birds.

"They do need to take the oil off the ship, and that is the priority," said Joanne Groenenberg, Maritime and Coast Guard Agency spokeswoman.

The process was expected to take about a week.

The British cargo ship was deliberately run aground close to the Devonshire resort of Sidmouth, 165 miles southwest of London, after it was damaged during a storm Thursday. Its crew of 26 was rescued, but at least 200 containers went overboard, including three carrying toxic materials such as battery acid and perfume.

"It's a challenging and difficult operation: The ship is listing, the decks are slippery, the hull has cracked, and it's resting on a sandbank," Groenenberg said, adding that over 200 coast guards were involved in the recovery operation.

Once the ship's fuel is drained, work can begin plucking the containers off the deck using a crane before the ship itself could be removed, a process she said could take up to a year or longer.

The beach was quieter Tuesday, a day after hundreds of people descended on the containers that had washed ashore, taking away items such as motorcycles, tennis shoes and barrels of wine. They left piles of plastic wrapping, pieces of cars, broken containers and discarded diapers.

"It's a complete mess... it looks like a landfill site," Groenenberg said. "If they had left the stuff in the containers, the clean-up may been easier."

No arrests had been made, said another Devon and Cornwall police spokesman, Baxter Provan. The lure of the beached treasure had generated enormous interest, he said.

"We were getting reports of people coming from all over the (United Kingdom) to comb the beach," Provan said.

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